Power transmission coupling



FIG. 1 is a front perspective view of a power transmission coupling;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof;

FIG. 8 is a cross-sectional view thereof taken along the line 8-8 FIG. 6; and,

FIG. 9 is a cross-sectional view thereof taken along the line 9-9 in FIG. 4. 

CLAIM The ornamental design for a power transmission coupling, as shown and described. 